Orthopedic exerciser

Abstract

An orthopedic apparatus for rehabilitation or healing of a knee or the muscles of a leg. The apparatus has a dynamic adjustment mechanism allowing the execution of exercise of different degrees of tension without running the risk of injuring the knee by applying unnecessary or excessive amount of tension on the knee. The dynamic adjustment mechanism is designed to keep the eccentricity of the rotational axes of the leg support member and the leg nil. The orthopedic apparatus may also include a resistance or assistance mechanism for adjusting different degrees of tension during extension and flexion of the leg in order to gain either range of movement or strength. This specially designed mechanism provides a linear type resistance or assistance, which is invariable during the whole range of movement. This particular resistance, applied on the plantar foot, reproduces normal bio-mechanical stress on the lower limb. The exerciser may further include a blocking mechanism for allowing instant pause and prevents reversal of the movement during the exercise. Finally, the exerciser may still include a static adjustment mechanism for adjusting the leg support member to a predetermined length.

What is claimed is:  
     
       1. In an orthopedic apparatus for resistive extension and flexion of a user's leg the orthopedic apparatus comprising a main frame having a pair of rails, a leg support member having a first end fixedly secured on said main frame and a second end slidably mounted on said pair of rails of said main frame, said leg support member comprising a first portion designed to receive the user's thigh, a second portion designed to receive the user's shank and a third portion designed to receive the user's foot, said first and second portions each comprising two opposite side edges defining the width of said leg support member, said first and second portions further being pivotally connected to each other and forming a rotational axis for allowing flexion of the user's knee, wherein the improvement comprises 
       a dynamic adjustment mechanism in the form of an indented hinge between the first and second portions for minimizing tension on the user's knee during extension or flexion of the user's leg, said mechanism allowing substantially no eccentricity between the user's knee and the rotational axis,  
       said first and second portions being pivotally connected together so that when the user's leg is flexed and extended, the user's knee and the rotational axis are substantially coincident throughout the range of motion.  
     
     
       2. In an orthopedic apparatus according to claim  1 , further comprising a resistance mechanism for allowing adjustment of different degrees of tension during extension and flexion of the leg. 
     
     
       3. In an orthopedic apparatus according to claim  2 , comprising a blocking mechanism for allowing instant pause of the extension and flexion of the leg and prevent temporary undesired reversal of movement. 
     
     
       4. In an orthopedic apparatus according to claim  3 , further comprising a static adjustment mechanism for adjusting said first and second sections to a predetermined length. 
     
     
       5. In an orthopedic apparatus according to claim  4 , wherein said static adjustment mechanism comprises a pair of internal and external tubes, the internal tubes being adapted to fit and slide inside a pair of external tubes, said internal and external tubes forming said side edges of said first and second portion respectively. 
     
     
       6. In an orthopedic apparatus according to claim  5 , wherein said static adjustment mechanism further comprises a spring-knob on one end of said internal tube and a plurality of holes at a corresponding end of said external tube of said first and second portions. 
     
     
       7. In an orthopedic apparatus according to claim  2 , wherein said resistance mechanism comprises a pair of pistons, each of said pistons having a first end connected to a portion of said side edge of said leg support member and a second end connected to a portion of said main frame. 
     
     
       8. In an orthopedic apparatus according to claim  3 , wherein said blocking mechanism comprises a ratchet wheel and a rack, said ratchet wheel having a first and a second lever. 
     
     
       9. In an orthopedic apparatus according to claim  1 , wherein said pair of rails is further provided with adjustable stoppers in each rail for limiting the range of motion during flexion and extension.